Known starting elements for the combustion process in an internal combustion engine, such as a spark plug or a sheathed-element glow plug, include a ceramic element. Until now these ceramic elements were coated with a slip in a wet process, for example using a casting, dipping, spraying, sprinkling or roll-on method. Once the slip has been applied, the ceramic element is fired, the bakable material contained in the slip fusing or sintering to form a vitreous layer, often also referred to as ceramic layer.
However, a disadvantage of such wet chemical treatment methods is that the manufacture of the slip is comparatively expensive, that fouling processes may destroy the slip and that sedimentation processes must be counteracted, which results in waste-water problems and high energy consumption. Draining slip may form droplets and necessitate expensive aftertreatment. In heaters for a sheathed-element glow plug of a diesel engine the draining slip may result in a thin layer thickness, thereby increasing the danger of a short circuit.